


Summer Lovin'

by scarletmanuka



Category: Sherlock (TV), Sherlock Holmes & Related Fandoms
Genre: Consensual Underage Sex, Day At The Beach, Fluff and Angst, M/M, Mycroft has Low Self Esteem, Prompt Fill, Sherlock has a cunning plan, Sibling Incest, Summer, Teenlock, holmescest
Language: English
Status: Completed
Published: 2017-09-25
Updated: 2017-09-25
Packaged: 2019-01-05 06:51:23
Rating: Explicit
Warnings: Underage
Chapters: 1
Words: 6,859
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/12185046
Author URL: https://archiveofourown.org/users/scarletmanuka/pseuds/scarletmanuka
Summary: For the prompt by Sugabee_Lara : 'Summer Teenlock Prompts (I’m late but it’s almost summer in the south hemisphere okay): Mycroft has to go shopping for bathing suits with his little brother, the AC is broken, they spend a day at the beach together and Sherlock wants Mycroft to help him put on sunscreen, they have to go on a roadtrip...'





	Summer Lovin'

“I’m dying.”

“No, Sherlock, you’re not.”

“I am. I’m dying, Mycroft and it’s the most horrible way to go.”

“If you don’t stop your whining I’ll be happy to demonstrate a properly horrible way to die.”

“Oooh! Please show me how to kill someone!”

“You do realise that I’ll be demonstrating on  _ you _ and therefore you will be dead. And silent. Blissfully silent.”

“Being dead doesn’t sound so bad at the moment.”

“No?”

“It’s better than  _ dying  _ and that’s what I’m doing, Mycroft. It’s dreadful.”

“For the last time, Sherlock - you are  _ not _ dying.”

“Yes I am. I’m melting. Like a witch.”

“More like a little bitch.”

“What was that?”

“Nothing.”

Sherlock sat up and glared at his older brother and then flopped back down onto his back on the patch of grass he was occupying under the largest tree on the grounds. He wiped a bead of sweat from his brow and then threw an arm over his face dramatically. “It’s  _ so hot _ . Why does it have to be so damn hot?”

His older brother sighed and put down the book his was reading. He was perched in a fold out sun chair, not wanting to get his crisp linen trousers dirty from the lawn. He was also wearing a short sleeved cotton shirt and the top two buttons were undone due to the heat. “Because it’s summer, Sherlock. It happens every year so there’s no need to act so surprised.”

“Yes, but normally the air conditioning isn’t on the fritz,” he grumbled. He rolled over onto his stomach, not caring if he got grass stains on his own shorts and t shirt. He plucked free a blade of grass and absently began to shred it. “Will you show me?” he asked out of the blue.

Mycroft had returned to his book and he lay it in his lap again with an exasperated sigh. “Show you what?”

“How to kill someone. Horribly. Obviously.”

“What on earth makes you think that I actually know how to kill someone?”

He rolled his eyes. “We both know you work for the Secret Service, you don’t have to pretend with me that it’s a ‘minor position in the British Government’. I know it’s not.” He’d lifted his hands to make air quotes, his legs bending upwards to counter balance himself as he took his weight off his elbows.

His brother’s blue eyes darted around the yard but Sherlock was sure no one but someone as observant as himself would have caught it. “You’re being ridiculous. I’m a clerk, brother mine, nothing more.”

“Uh huh, sure. And I’m Queen Elizabeth.”

“You’d look rather fetching in one of her dress suits.”

He smirked and fluttered his eyelashes. “That’s because I’m so achingly pretty.”

Mycroft swallowed hard and looked away, ignoring the comment. Sherlock’s heart gave a little lurch, yet another piece of evidence that his brother felt more for him than he should. He’d been holding out hope but knew that Mycroft would never admit it or act on it, too prim and proper to take advantage of his fifteen year old brother. It was getting to the point where the teen would have to take matters into his own hands and make the first move. He had no idea how, but dammit, he  _ wanted _ Mycroft and he was used to getting what he wanted. His brother had taken leave to spend with the family over Sherlock’s summer break from school and he was determined that before Mycroft returned to London,  _ something _ will have happened.

“Are you going to tell me how to kill someone in an excruciating manner or not?” he asked, making sure his brother wouldn’t escape into his book to avoid the tension that had suddenly sprung up between them.

“Who do you want to kill so badly that a knife between the ribs wouldn’t suffice?”

“If you don’t stop avoiding the subject,  _ you _ for starters.”

“Then it seems in my best interests  _ not _ to teach you.”

“Please, My?  _ Please? _ ” he wheedled, making his eyes as big and round as possible.

“I’m not going to teach my baby brother how to become an assassin,” he retorted.

“Hah! So you  _ are _ an assassin!”

“What? Of course I’m bloody not! Where on earth do you get these insane ideas?”

“Once you’ve eliminated the impossible, whatever remains, no matter how improbable, must be the truth.”

“Bollocks.”

“Well, you’re definitely not just a clerk.”

“But you are most definitely a brat.”

“And you are an assassin!”

“Sherlock, I’m not, though if you continue on this path, I  _ will _ be a convicted murderer.”

“Boring!”

Mycroft threw his hands into the air. “Don’t you have something else you could be doing?”

“No, because I’m dying!” He rolled over onto his back once more. “It’s  _ so hot _ . Tell me what you do as a super spy so I’m distracted from the heat?”

“Aaargh! You are infuriating!” Mycroft stood up suddenly. “Let’s go to the beach,” he announced.

Sherlock scrambled up onto his knees. “What? Are you serious?”

“Of course I am. You want a distraction from the heat and so swimming should suffice.”

“But you  _ never _ swim.” Mycroft had been a chubby teen and avoided swimming whenever possible. Sherlock used to beg and beg for him to come in he water with him when they went to the lake, but he always refused. He was cripplingly shy when it came to wearing a bathing suit, and even as a child, Sherlock could tell he had massive self esteem issues. He’d never understood why - big or small, Mycroft was the most beautiful person Sherlock had ever seen. The way his mind worked, how fast he connected the dots, the way he could tear an argument to nothing, these were all more important things than what size shirt he wore. The teen wasn’t blind to physical attributes though; Mycroft’s gorgeous eyes and long, delicate fingers often appeared in his daydreams and fantasies.

“That doesn't mean you can’t swim, brother mine. I’m happy to watch from the shore.”

“We’re not driving for two hours to get to the beach for you to just sit on the sand! If we’re going, then you have to promise me you’ll swim with me.”

“I don’t even having a bathing suit, Sherlock.”

“There are shops on the way.”

“You know I burn so easily in the sun.”

“Yet again, shops on the way. Sunscreen and a hat will protect your freckles.”

Mycroft bit his lip, torn. It took a long time but eventually he assented with a short nod of his head. “Very well. We’ll have to leave immediately if we’re to make it in time.”

Sherlock grinned, already on his feet and running towards the house. He hadn’t given up on pressing for answers about the true nature of his brother’s work, but he knew when to pick his battles. If he asked while they were  _ at the beach _ , Mycroft couldn’t threaten to not take him.

It wasn’t long before they were sliding into Mycroft’s old Jag and were off. Although his brother had access to his trust fund, he refused to touch it, insisting on making his own way and keeping the family money for his retirement. He’d saved every penny when he first started working, taking the tube or walking to work until he could afford an old car. It wasn’t in the best shape but it did the job and Sherlock was impressed that any minor mechanical issues that arose, Mycroft fixed himself. The last time his brother had come to visit, Sherlock had stumbled across him leaning over the bonnet, head and shoulders hidden from view but his plush arse very prominently on display. He’d ogled him for a good five minutes before Mycroft surfaced and asked him what he was staring at. There was a smear of grease over his left cheek and he was dressed in jeans and a plain white t shirt and Sherlock had been unable to answer, his mind too busy inserting the scene into his naughtiest fantasies. Mycroft had shrugged it off as one of his baby brother’s eccentricities, and Sherlock had run off to room to have an immediate wank.

Just the memory of that day made him grow harder in his pants, and he shifted slightly on the seat, hoping to discreetly adjust himself. Mycroft didn't seem to notice, concentrating on finding the exit to the nearest shopping centre. It took an age to find a park, the masses flocking to the air conditioned comfort of the complex. They made their way across the scorching bitumen and when they stepped through the automatic doors, both brothers sighed in relief as the cold air hit their flushed faces. They went to the nearest department store and quickly found the men’s section.

Mycroft immediately went to the rack of board shorts, while Sherlock browsed the more traditional suits. He held up a lime green speedo wordlessly and waggled his eyebrows at Mycroft, causing his brother to laugh. “I think not, brother mine.” 

He put them back on the rack. “Shame,” he muttered under his breath.

“I’m going to go and try these on,” his brother said, holding up three pairs of shorts.

“I’ll come,” Sherlock said. “The urge to redress the mannequins in something inappropriate is growing stronger and I don’t particularly feel like spending the afternoon with security.” It was a lame excuse but it did the job. There was no way he was going to miss the opportunity to perv on his brother in a changing room.

Of course, Mycroft made him sit outside on one of the ottomans that lined the corridor. Feeling miffed at being denied his chance, he lounged with his arms crossed over his chest and a pout on his face. Then he heard the noise of discontent from the change room. “What is it?” he asked.

“I don't know about any of these,” Mycroft muttered.

“Why not?”

There was a heavy sigh. “I’m just not overly comfortable in shorts.”

“I won’t be seen dead with you in a full wet suit, My. I’m sure it’s not as bad as you think.”

“You say that now but when I’m sitting on the sand and activists start throwing buckets of water over me, mistaking me for a beached whale, you’ll change your tune.”

He huffed, knowing that Mycroft had lost almost fifty pounds over the past several years. His brother seemed unable to see the difference in his physique though, only seeing the chubby teen he once was. Sherlock stood and crossed to the cubicle, his hand resting on the curtain. “May I?” he asked.

There was a sigh. “If you must.”

He stepped inside and pulled the curtain closed behind him. He immediately spotted the problem and tried not to roll his eyes. “Give me a look,” he murmured, stepping into Mycroft’s personal space. He noticed the sharp intake of breath and the way his brother’s pupils dilated but he ignored that for now, concentrating on the task at hand. The pair of shorts his brother had on were black with blue panels down the side and looked nice enough, except for the fact that the material billowed out from underneath his shirt. Sherlock took hold of the hem of the shirt and lifted it up, ignoring the gasp from Mycroft. “They’re way too big,” he stated, slipping a finger under the waistband and pulling it outwards. He tried to ignore the amount of skin he could see, so close, begging to be touched. His whole hand was tingling just from the barest brush of his finger over Mycroft’s hip.”I’m going to go and get you a smaller size.”

“I prefer them to be loose,” his brother protested.

“They’ll look better if they’re the right size,” he contradicted him. “Besides, board shorts loosen once they’re wet so they should be a bit tight.” Before he could answer, Sherlock stepped out of the cubicle and headed back to the racks, skipping the next size down but getting the next two after that. He returned to the change room and slipped back inside, just in time to catch Mycroft looking at his reflection in despair. He knew that no matter what he said, he wouldn’t be heard, or his brother would assume he was being flippant and sarcastic, so he remained quiet. “Here, try these on,” he said, handing over the smallest pair. 

Sherlock turned his back and pretended to be very interested in the weave on the curtain, hoping that Mycroft wouldn’t kick him out. He didn’t, and when he clicked his tongue, the teen took that as a sign he was now dressed. “I don’t know,” Mycroft said, his eyes downcast, avoiding the mirror.

Sherlock lifted his shirt again, slightly higher this time and hummed happily. “These are much better,” he said, slipping a finger through the waist again, relishing the feel of that soft skin.They were still a little big but he knew Mycroft wouldn’t go down another size so there was no point even trying. He stepped sideways a little, still holding the shirt up and out of the way, moving so he could see how they fit at the back. He could feel his heartbeat speed up as his eyes trailed over the lush curve of Mycroft’s arse and he couldn’t help but run a finger under the band at the back, brushing it along the width of the small of his back. 

“They’re okay?” Mycroft asked quietly.

“Oh yes,” Sherlock replied, in a much more breathy voice than he ought to have used in such company. “They look good.” He stepped back around to the front, still holding his brother’s shirt out of the way and he trailed a finger over the taut stomach. The only signs remaining of his previous weight were very faint stretch marks on his hips and he couldn't understand why Mycroft couldn't believe how much he’d changed. “ _ You _ look good,” he said. “But then again, you  _ always _ looked good.”

Mycroft flushed a deep red and then turned to grab his linen trousers. “Um, well, I suppose I’ll get these then,” he stammered. “I won’t be long.”

Knowing he’d pushed it a little too far, Sherlock nodded in silence and left the cubicle, allowing his brother to change. He emerged a few moments later and they left the unwanted items on the returns rack and then headed to the cashier with the shorts, stopping on the way to get a tube of sunscreen. Sherlock made them also stop at a store in the food court that sold slushies and they got one each to help them once they returned outside into the scorching heat. 

The drive to the beach was quiet, Sherlock’s attempts at conversation falling flat. He felt sick, wondering if he’d misread the situation. No, that wasn’t it. He  _ knew _ Mycroft was attracted to him, he had plenty of evidence to support that, so it must be something else. Likely the fact that Sherlock was so much younger than him. He was certain it wasn’t the fact that they were both brothers - neither of them gave a flying fuck about society’s conventions when it concerned such trivial matters. The age thing though...he was sure that that was what Mycroft was rebelling against. That  _ wasn’t _ just a trivial convention, but a rather formidable law. As much as he wanted this, would willingly give his consent, the fact of the matter was the law considered him to be a child and Mycroft could be charged with statutory rape.

If they were caught, that is. Sherlock was confident that given their intelligence they would have few issues in keeping such a clandestine affair hidden. They were some of the smartest minds of their generation, and that wasn’t even Sherlock’s cockiness or arrogance speaking - tests proved it to be true. If anyone could keep this hidden, it was them. He just had to convince Mycroft of that fact. He knew he would have an easier time of that when they were alone and so he began to formulate a plan to give him more time.

They finally made it to the beach in the early afternoon. Sherlock’s stomach was grumbling and he insisted that since they were at the seaside, they have fish and chips. His brother agreed and they headed to the chip shop, only to find a line out the door. Of course the beach was packed due to the heat and everyone had the same idea. The teen protested when Mycroft suggested they go somewhere else, stubbornly insisting on fish and chips. He knew his brother would not be able to deny him anything and so they stood patiently in line. 

After a few minutes, Sherlock made a show of checking the bag he’d packed. “Darn it, I’ve left the sunscreen in the car. Can I have the keys?” 

Mycroft handed them over and Sherlock left him there in the queue, heading back to the carpark. He stopped by one of the bins on the way, quickly finding what he was after. He got to the car and with a quick look around to make sure there were no witnesses, he smashed the bottle he’d found in the rubbish on the ground behind the car. He picked up a larger piece of glass and stabbed it into the left rear tyre, and then found another piece and did the same with the right rear. He knew that the Jag had room for one spare, but with two damaged tyres, they would have no choice but to stay until they could buy another. He intended to discover the car well after the shops had closed for the night, forcing them to find somewhere to stay. It was a little underhanded, and it was risky - Mycroft was just as observant as he was and so he may realise that he hadn’t reversed over any glass when parking, but he was willing to take it. Even if his brother did figure out that Sherlock had sabotaged the car, they would still be stranded until morning and so he’d still get the time he wanted.

Satisfied with the job, the teen headed back to the boardwalk and found Mycroft waiting outside the shop. He had a numbered ticket in hand and was leaning against the railing. Sherlock joined him, standing close, their hips brushing. “So, how many ways could you kill someone using only a fillet of cod?” he asked suddenly.

Mycroft turned to give him an incredulous look, causing their arms to press together as well. “You do know it’s a little disturbing that you’re so obsessed with death,” he said instead.

“From what I’ve researched, I’m a high functioning sociopath so that’s to be expected.”

“No, you’re not, and no, it isn’t.”

“I’m fifteen now so the definitions can be applied to me.”

“One, you can only be diagnosed once you reach  _ eighteen _ , you just have to have been showing symptoms from age fifteen. Two, being obsessed with death isn’t one of the diagnostic tools of antisocial personality disorder. And three, don’t mistake your high level of analytical thinking for being unfeeling. You are one of the most compassionate people I know, Sherlock and most assuredly  _ not _ a sociopath.”

He snorted. “I am  _ not  _ compassionate.”

“Says the boy who just spent half an hour in a fitting room convincing me I wasn’t a whale.”

There were several things he wanted to reply to that -  _ ‘I’m not a boy’, ‘You’re not a whale’, and ‘That doesn't prove anything _ ’. Instead he found himself asking, “And did I? Convince you?”

Mycroft turned back to face forward, a small smile tugging at his lips. “Maybe.”

“Number fifty seven!” a voice shouted out from the counter and Mycroft pushed off from the railing to collect their order. 

He’d taken four steps but he paused and looked back. “Four,” he said cryptically.

“Huh?”

“You wanted to know how many ways I could use a fillet of cod. It’s four.”

Sherlock threw back his head and laughed, not sure if Mycroft was being serious or not but not caring. His brother was grinning when he came back, a parcel wrapped in paper in his hands. “Where shall we eat?”

“Let’s walk down to the end of the dock, then we can find somewhere to get changed and go for a dip.”

The wandered down the crowded boardwalk, making their way to the very end and sat with their feet overhanging the side, the fish and chips nestled between them. The food was delicious and Sherlock sucked the grease and salt from his fingers. He caught Mycroft’s widened gaze on him and knew his brother was enjoying the show, so he did it again, adding a slight moan as he did so. “These chips are divine,” he added innocently, popping a large one on his mouth and sliding it between his lips. 

“Yes, they are quite good,” his brother replied in a hoarse voice, tearing his eyes away and focussing on the piece of fish in his fingers.

The teen didn't push it any further, knowing he'd had a victory of sorts. They finished their lunch but sat a while longer, throwing leftovers to the gulls and watching the birds soar and squark as they fought over the fish. “Do you enjoy your work?” Sherlock asked, seriously for once.

Mycroft pulled a chip into pieces and lobbed it into the water. “Yes, I do. I have plans, and this is just a stepping stone for my ambitions. I don’t overly enjoy legwork but I admit there is some satisfaction in being able to use my brain to best the enemy.”

It was the closest he’d ever come to admitting to working for the secret service. A sudden, terrifying thought occurred to Sherlock. “Is it dangerous?”

Mycroft shrugged. “Sometimes. I’ve not been hurt too badly so far.”

“If that was meant to be reassuring, you did a shitty job.”

He chuckled. “When have I ever kept the truth from you, even if it wasn’t pleasant?”

“You tend to not lie, I’ll give you that, but you don’t always tell me everything either.”

“Yes, well, that’s why they use the word ‘secret’. I’d be rubbish at my job if I went around shouting from the rooftops everything I did.” He seemed to decide that their conversation was over. Climbing to his feet, Mycroft reached a hand down for his brother to take and helped him to his feet. It was harder than it should have been for Sherlock to let go once he was standing. 

“I saw some change rooms at the start of the pier. Shall we get into our bathing suits?”

Mycroft tensed a little but nodded, hiding the flash of panic by turning around and heading off down the boardwalk. It seemed the work Sherlock had done earlier needed some polishing and he vowed that he’d do all he could to make his brother feel better about himself by the time they headed home. He followed after him, falling into step beside him but staying silent. When they reached the change rooms, he didn’t say anything either when Mycroft chose to go into one of the toilet cubicles to get changed instead of doing it in the main room. 

Mycroft emerged, holding his clothes in a bundle against his bare chest, obviously uncomfortable. It was enough to make the teen push aside his own selfish desires and put his brother first. “We don’t have to go swimming if you really don’t want to,” he said softly, stepping close so the men on the other side of the room wouldn’t hear.

“No, it’s alright.”

“I know it is. We can change back into our other clothes and just go for a walk along the water’s edge.”

“We’ve come all this way, Sherlock, so we may we well go swimming.”

“But we don’t have to!”

“I know.” His eyes flickered over the teen’s bare chest before he glanced away. “Maybe I want to,” he mumbled.

Suppressing a grin, he reached out and gently took the clothes from Mycroft and shoved them into his bag. “Come on then, let’s go.”

They walked down the stairs to the beach, the coarse sand hot beneath their feet. Sherlock was glad they chose to come here - there were other beaches much closer to home but most of those had pebbles or rocks instead of sand and this was much nicer. They found an empty patch of sand and he shook out his towel, then settled down onto it. He pulled the tube of sunscreen from the bag and handed it to his brother who was also laying out his towel. “Will you do my back?” he asked.

Mycroft gave a short nod and took the tube, squeezing a large dollop onto his hand while Sherlock twisted around so he was sitting just inside the V of his brother’s legs. The first touch was hesitant and he could feel the way Mycroft’s fingers trembled. He folded his arms on top of his knees and rested his face on them, enjoying the feel of those hands finally being on him. Mycroft was thorough, spreading the cream over his skin and then rubbing it in, not hurrying and doing a subpar job, but not moving as quickly as he could have done. Sherlock was sure he was enjoying it as much as he himself was, though he would probably never admit it. Once his back was covered, Mycroft handed him the tube back so he could do his front. 

“Would you like me to do yours?” he asked once his chest and face had been lathered.

Despite it being a given that he would require assistance lest he burn to a crisp, Mycroft still hesitated before he nodded. He turned around on the towel, his back to the teen but still quite a distance from him. Tutting, Sherlock scooted closer, his legs to either side and his groin only  _ just _ brushing against Mycroft’s arse. With a nonchalance that he didn’t quite feel, he squeezed the sunscreen onto his hand and then slathered it over Mycroft’s back. He put both hands to the task, not just smoothing it over the freckled back, but massaging it in. Mycroft moaned and his head fell forward onto his knees as Sherlock worked at a particularly hard knot under his shoulder. He felt the tight muscle loosen and give way and he moved on to the next knot. By the time he’d worked most of them free, the sunscreen had long been rubbed in and his brother was close to falling asleep. He reached for the tube again, tightening his knees around Mycroft’s hips as he tried to move away. “I’m not done yet,” he murmured. 

His brother relaxed back a little and Sherlock squeezed more cream onto his fingers then reached up and made sure that his brother’s neck and ears were covered. He then worked his way down his arms, smoothing his hands repeatedly down over them, feeling the muscles under his fingers as he did so. The next time he ran his hands down, his fingers circled Mycroft’s wrists and he brushed his thumbs over his pulse point before trailing back up, leaving goosebumps in their wake. 

“Now I’m done,” he said, not making any attempt to move away.

“Thank you.”

“Any time. Shall we swim?”

“Um, maybe not just yet. It’s nice here in the sun so perhaps we can just enjoy it for a few minutes?”

He smirked unseen behind his back, knowing that Mycroft was likely just as hard as he was and not wanting to skip down to the ocean with a raging erection. “Sounds nice.” Then he leaned forward and wrapped his arms around Mycroft, resting his face on his back.

“What are you doing?” Mycroft asked in a halting voice.

“Am I not allowed to give my brother a hug?” he asked innocently. “You’ve driven me all the way to the beach after all. I should be allowed to say thanks.”

His hand was given a cursory pat. “It’s okay, I was happy to do it.”

“And I just want you to know how much I appreciate it. You’re an awesome big brother.”

“Sherlock?”

“Yes, Mycroft?”

“Giving me hugs and sweet talking me isn’t going to make me tell you about my job.”

He laughed and pulled away, rolling so he was sprawled on his stomach and hiding his hard on. “Well, it was worth a try,” he said, pretending that that had been his motivation. He was pretty certain that his brother didn’t believe it was either but if pretending made it less awkward, then he was happy to play along - for now. 

Mycroft copied his pose, lying on his tummy as well. “I’d be disappointed if you didn't try.”

“Of course you would - you taught me better than that.”

“I tried my best. Of course, there’s only so much you’d listen to me.”

“Well, you do waffle on.”

“Only to you. No one else can keep up.”

“So I’m supposed to be honoured that you never shut up?”

“Naturally.”

“Just as long as you don’t get offended when I tune you out after a while.”

“Certainly not. I know my intelligence is too much for even you to comprehend so whatever you can keep up with, brother dear.”

Sherlock flicked sand at him. “Bastard.”

“Brat.”

“You already used that insult today. You’re slipping.”

“If the shoe fits…”

They grinned at each other, both enjoying the banter. It was one of the things Sherlock missed most when Mycroft went off to London for work. He lay his head down on his arms, enjoying the warmth on his back but after a while it began to burn. His erection had completely disappeared so it was safe enough to make a dash for the water. He stood up and stretched. “I’m going in now. You coming?”

“I suppose so.”

“Such enthusiasm.”

“I promised to swim, not to enjoy it.”

The teen bit his lip, silently betting he could make Mycroft enjoy himself by the end of their swim. He grabbed Mycroft’s hand and tugged. “Come on then.”

They hurried across the hot sand, both flinching as the cold waves lapped over their feet. It was an odd contrast - the sun burning their skin, the water so icy that it caused goosebumps to race up their legs. He saw Mycroft hesitate, not wanting to go in any further and he decided that if he was going to be called a brat anyway, he may as well live up to the name. He leapt at his brother, tackling him around the waist, the momentum carrying them over and into the waves. Mycroft stood up, soaked and spluttering, his eyes wild. “You little shit!” he cried, lunging for the teen.

Sherlock shrieked and turned to flee but his brother was faster, grabbing him by the shoulders and dunking his head under the water. Sherlock surfaced, unable to keep the grin off his face and raised his fist with the handful of sand he’d scooped up from the seabed, flinging it at his brother’s face. Mycroft roared and came after him again and soon they were in a full scale battle. It raged for half an hour, the current moving them away from the spot they had entered the water. They got close to the rocks that jutted out from the shore and there were hardly any swimmers here, so their play fight didn't disturb anyone else. 

After they’d called a truce, they climbed up onto the rocks and took turns diving into the water, their competitive nature driving them to collect shells and rocks from the seabed. Sherlock lay sprawled on a flat rock, watching as Mycroft dove under the water, watching a school of fish that were swimming around his legs. He was unable to keep the smile off his face, thoroughly enjoying their afternoon and the way his brother truly relaxed. Ever since he had started his work, he always seemed to be slightly on edge, always having to have one eye open. Here he was carefree and happy, just enjoying a leisurely afternoon. He surfaced from his dive, having moved to shallower waters as he'd followed the fish. The water only came up to his bellybutton and Sherlock couldn't help but stare as rivulets streamed off his chest and shoulders, and how his toned arms flexed as he ran a hand through his hair to push it back from his face. Sherlock’s swim shorts were getting tighter and he knew he'd have to plunge into the cold water again to take care of it. He stood up and dove in a graceful arc into the water, slipping under it with barely a splash. He opened his eyes as he moved through the clear water, making out his brother’s legs a short distance away. He kicked hard and aimed himself and then he was there, pushing his way through those lean legs. He felt Mycroft jump and then a hand was in his hair and he was being yanked to the surface.

“You scared the ever loving shit out of me!” Mycroft scolded, though he was trying not to laugh so he’d obviously found it funny.

Sherlock grinned. “There wasn’t any theme music so you should have known it wasn’t a shark.”

“You’re such a menace that you need your  _ own _ theme music.”

“I shall begin composing as soon as we get home.”

“I look forward to hearing what you come up with.”

They spent the next hour observing the fish and studying the molluscs that clung to the rocks. It was starting to get late and Sherlock noticed that the crowds were thinning, leaving very few people at the beach. Mycroft would probably suggest they leave soon but he was having too much fun and wanted to stay. Besides, he had to delay them getting back to the car too soon. He saw a large fish swimming around his brother’s feet and pointed to it, before taking a large breath and diving under the water. He swam right at Mycroft’s feet, the fish startling and swimming away but he continued on, worming his way between his brother’s legs once again. This time though he grasped the hem of the board shorts and tugged. As he’d known would happen, the material had gotten extremely loose when it was weighed down with water and they slipped easily off his brother’s hips. Using Mycroft as an obstacle course had left his brother off balance and a harder tug on the material sent his legs floating up off the seabed. As he swam up to the surface, he pulled and the shorts came off his brother’s legs completely. He got a quick look, enough to see that Mycroft hadn't bothered with underwear beneath his bathing shorts and then he was surfacing, taking a deep breath and holding his prize above his head with a smug grin. “Dacked you!” he announced.

“Sherlock! You give them back!” Mycroft snapped, ducking down lower into the water and looking around in a panic to see if anyone had noticed he was suddenly naked.

“Nope,” he said, popping the p.

“I’m warning you! You give them back right this instant.”

“You want them? Take them.” He swam out into deeper water, the shorts clutched in his hands. He heard a splash behind him and then a hand grasped his ankle, hauling him backwards. His whole upper body was dragged under the water at the force and he came up coughing up water. “No fair!” he said in between coughs.

“I don’t play fair, little brother.” Mycroft growled, lunging at him.

Sherlock held the shorts as far away as he could, just out of his reach. “Neither do I.”

They wrestled a little more and then Sherlock decided it was time to show his brother just how unfair he did play. He jumped up, wrapping his arms around Mycroft’s neck and his legs about his waist. Mycroft’s hands automatically dropped to his arse to support the person clinging to him, even though the buoyancy made it redundant. His blue eyes were open wide and his face was shocked. “What are you doing?” he asked in the quietest voice possible, as if he wasn’t sure he wanted to hear the answer.

“What I’ve been wanting to do for years,” Sherlock replied and then leaned forward and kissed him.

He had honestly expected his brother to reject him; to push him away, tell him it wasn’t allowed; to yell and scream and get angry. Instead Mycroft just gasped and pressed them closer together, deepening the kiss and licking his way into Sherlock’s mouth. It was an unexpected surprise and Sherlock returned the kiss greedily, drinking in the experience he had been dreaming about for so long now. He started to even think that he  _ was _ dreaming as the kiss went on and on, better than he’d ever imagined and everything he’d ever wanted. Then there was a hand dipping down into his shorts and groping his arse and he knew that it was very real. This was happening and he was ecstatic. 

Sherlock tightened his legs around Mycroft’s waist and ground his hips down, feeling his brother’s erection pressing against his arse. He suddenly wanted to feel even more and he let his legs go and allowed his body to float backwards so he could shimmy out of his own shorts. He balled them up along with Mycroft’s and lobbed them at the rocks, not wanting them to get swept away by the tide. Happy that they would have clothes to get changed back into, he moved his legs back until they were once more wrapping around Mycroft. Skin to skin was electrifying and he gasped as Mycroft’s cock dragged against the cleft of his arse. His own cock was trapped between their stomachs and so he rutted against Mycroft, looking for some sort of friction, even as their lips found each other once again. 

They kissed and they touched, caressed and stroked, licked and nibbled, rutted and gasped, and soon their release was shooting into the ocean and the cloudy mess was washed away with the waves. He clung to Mycroft, both of them breathing hard and starting to shiver from the cold. “Come on, brother mine. We should get home. I think we have a lot to talk about and the drive back will give us ample time to figure out how this is going to work.”

“You mean you want to be with me?” he asked in a small voice, still unable to believe it.

“Of course I do, Sherlock. Was this not proof enough? Do you think I’d have let it go this far if I wasn’t serious about wanting to be with you?”

“You could get in trouble,” he warned, unsure why he was arguing and not just accepting his good luck.

“I know, and I take that very seriously. You’re only fifteen...people will think I coerced you…” He trailed off and swallowed hard.

“You didn’t, and they won’t find out,” Sherlock assured him. “We won’t let anyone find out.”

Mycroft nodded and then smiled. “In this together?”

“Always.”

“Excellent. Shall we go home?”

“Um, about that…”

He sighed. “What did you do?”

“I thought I’d need more time to convince you, so I may have disabled the car.”

“How did you manage that?”

“I stabbed two of the tyres,” he admitted sheepishly.

Mycroft threw back his head and laughed, and his younger brother couldn't help but join in. “If that doesn’t make this premeditated, then I don’t know what would,” he said when he finally stopped laughing. “Oh, Sherlock. You could have just said something.”

He blushed and ducked his head, suddenly feeling very silly.

There was a hand under his jaw and his face was lifted until he was looking directly into those pale blue eyes. “However, I think I prefer this way. It was a rather enjoyable plan after all.”

He smiled shyly. “I’m glad you enjoyed it.”

“How could I not?” Mycroft arms were wrapped once again under Sherlock’s arse, supporting him against him and he let his hands wander and squeezed both cheeks. “How about we get out of the water then, dry off, and find a hotel for the night? Was that the way your plan was meant to go?”

“Something like that.”

Mycroft kissed him and held him tight. “It was a very cunning plan, brother mine. How about we put it into motion right now?”

“I’d like that very much.” 

One last kiss and they were swimming towards the rocks where their shorts had been thrown, Sherlock overjoyed that he’d finally gotten his way. Perhaps he should have made the effort to break the air conditioning  _ last _ summer instead, but since it had all worked out how he wanted, there was no point dwelling on the what could have beens. Instead he found himself looking forward to the future. 

  
  
  


**Author's Note:**

> Check out this awesome [moodboard on Tumblr](https://laralocked.tumblr.com/post/166353481531/moodboard-for-scarletmanukas-teenlock-fic-summer) by laralocked. I adore it :) Thanks, chicky!


End file.
